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 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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/*
 * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
 * (C) Copyright IBM Corp. 1996-1998 - All Rights Reserved
 *
 *   The original version of this source code and documentation is copyrighted
 * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
 * materials are provided under terms of a License Agreement between Taligent
 * and Sun. This technology is protected by multiple US and International
 * patents. This notice and attribution to Taligent may not be removed.
 *   Taligent is a registered trademark of Taligent, Inc.
 *
 */

package java.text;

import java.util.Vector;
import sun.text.UCompactIntArray;
import sun.text.IntHashtable;

/**
 * This class contains the static state of a RuleBasedCollator: The various
 * tables that are used by the collation routines.  Several RuleBasedCollators
 * can share a single RBCollationTables object, easing memory requirements and
 * improving performance.
 */
final class RBCollationTables {
  //===========================================================================================
  //  The following diagram shows the data structure of the RBCollationTables object.
  //  Suppose we have the rule, where 'o-umlaut' is the unicode char 0x00F6.
  //  "a, A < b, B < c, C, ch, cH, Ch, CH < d, D ... < o, O; 'o-umlaut'/E, 'O-umlaut'/E ...".
  //  What the rule says is, sorts 'ch'ligatures and 'c' only with tertiary difference and
  //  sorts 'o-umlaut' as if it's always expanded with 'e'.
  //
  // mapping table                     contracting list           expanding list
  // (contains all unicode char
  //  entries)                   ___    ____________       _________________________
  //  ________                +>|_*_|->|'c' |v('c') |  +>|v('o')|v('umlaut')|v('e')|
  // |_\u0001_|-> v('\u0001') | |_:_|  |------------|  | |-------------------------|
  // |_\u0002_|-> v('\u0002') | |_:_|  |'ch'|v('ch')|  | |             :           |
  // |____:___|               | |_:_|  |------------|  | |-------------------------|
  // |____:___|               |        |'cH'|v('cH')|  | |             :           |
  // |__'a'___|-> v('a')      |        |------------|  | |-------------------------|
  // |__'b'___|-> v('b')      |        |'Ch'|v('Ch')|  | |             :           |
  // |____:___|               |        |------------|  | |-------------------------|
  // |____:___|               |        |'CH'|v('CH')|  | |             :           |
  // |___'c'__|----------------         ------------   | |-------------------------|
  // |____:___|                                        | |             :           |
  // |o-umlaut|----------------------------------------  |_________________________|
  // |____:___|
  //
  // Noted by Helena Shih on 6/23/97
  //============================================================================================

  public RBCollationTables(String rules, int decmp) throws ParseException {
    this.rules = rules;

    RBTableBuilder builder = new RBTableBuilder(new BuildAPI());
    builder.build(rules, decmp); // this object is filled in through
    // the BuildAPI object
  }

  final class BuildAPI {

    /**
     * Private constructor.  Prevents anyone else besides RBTableBuilder
     * from gaining direct access to the internals of this class.
     */
    private BuildAPI() {
    }

    /**
     * This function is used by RBTableBuilder to fill in all the members of this
     * object.  (Effectively, the builder class functions as a "friend" of this
     * class, but to avoid changing too much of the logic, it carries around "shadow"
     * copies of all these variables until the end of the build process and then
     * copies them en masse into the actual tables object once all the construction
     * logic is complete.  This function does that "copying en masse".
     *
     * @param f2ary The value for frenchSec (the French-secondary flag)
     * @param swap The value for SE Asian swapping rule
     * @param map The collator's character-mapping table (the value for mapping)
     * @param cTbl The collator's contracting-character table (the value for contractTable)
     * @param eTbl The collator's expanding-character table (the value for expandTable)
     * @param cFlgs The hash table of characters that participate in contracting- character
     * sequences (the value for contractFlags)
     * @param mso The value for maxSecOrder
     * @param mto The value for maxTerOrder
     */
    void fillInTables(boolean f2ary,
        boolean swap,
        UCompactIntArray map,
        Vector<Vector<EntryPair>> cTbl,
        Vector<int[]> eTbl,
        IntHashtable cFlgs,
        short mso,
        short mto) {
      frenchSec = f2ary;
      seAsianSwapping = swap;
      mapping = map;
      contractTable = cTbl;
      expandTable = eTbl;
      contractFlags = cFlgs;
      maxSecOrder = mso;
      maxTerOrder = mto;
    }
  }

  /**
   * Gets the table-based rules for the collation object.
   *
   * @return returns the collation rules that the table collation object was created from.
   */
  public String getRules() {
    return rules;
  }

  public boolean isFrenchSec() {
    return frenchSec;
  }

  public boolean isSEAsianSwapping() {
    return seAsianSwapping;
  }

  // ==============================================================
  // internal (for use by CollationElementIterator)
  // ==============================================================

  /**
   * Get the entry of hash table of the contracting string in the collation
   * table.
   *
   * @param ch the starting character of the contracting string
   */
  Vector<EntryPair> getContractValues(int ch) {
    int index = mapping.elementAt(ch);
    return getContractValuesImpl(index - CONTRACTCHARINDEX);
  }

  //get contract values from contractTable by index
  private Vector<EntryPair> getContractValuesImpl(int index) {
    if (index >= 0) {
      return contractTable.elementAt(index);
    } else // not found
    {
      return null;
    }
  }

  /**
   * Returns true if this character appears anywhere in a contracting
   * character sequence.  (Used by CollationElementIterator.setOffset().)
   */
  boolean usedInContractSeq(int c) {
    return contractFlags.get(c) == 1;
  }

  /**
   * Return the maximum length of any expansion sequences that end
   * with the specified comparison order.
   *
   * @param order a collation order returned by previous or next.
   * @return the maximum length of any expansion seuences ending with the specified order.
   * @see CollationElementIterator#getMaxExpansion
   */
  int getMaxExpansion(int order) {
    int result = 1;

    if (expandTable != null) {
      // Right now this does a linear search through the entire
      // expansion table.  If a collator had a large number of expansions,
      // this could cause a performance problem, but in practise that
      // rarely happens
      for (int i = 0; i < expandTable.size(); i++) {
        int[] valueList = expandTable.elementAt(i);
        int length = valueList.length;

        if (length > result && valueList[length - 1] == order) {
          result = length;
        }
      }
    }

    return result;
  }

  /**
   * Get the entry of hash table of the expanding string in the collation
   * table.
   *
   * @param idx the index of the expanding string value list
   */
  final int[] getExpandValueList(int idx) {
    return expandTable.elementAt(idx - EXPANDCHARINDEX);
  }

  /**
   * Get the comarison order of a character from the collation table.
   *
   * @return the comparison order of a character.
   */
  int getUnicodeOrder(int ch) {
    return mapping.elementAt(ch);
  }

  short getMaxSecOrder() {
    return maxSecOrder;
  }

  short getMaxTerOrder() {
    return maxTerOrder;
  }

  /**
   * Reverse a string.
   */
  //shemran/Note: this is used for secondary order value reverse, no
  //              need to consider supplementary pair.
  static void reverse(StringBuffer result, int from, int to) {
    int i = from;
    char swap;

    int j = to - 1;
    while (i < j) {
      swap = result.charAt(i);
      result.setCharAt(i, result.charAt(j));
      result.setCharAt(j, swap);
      i++;
      j--;
    }
  }

  final static int getEntry(Vector<EntryPair> list, String name, boolean fwd) {
    for (int i = 0; i < list.size(); i++) {
      EntryPair pair = list.elementAt(i);
      if (pair.fwd == fwd && pair.entryName.equals(name)) {
        return i;
      }
    }
    return UNMAPPED;
  }

  // ==============================================================
  // constants
  // ==============================================================
  //sherman/Todo: is the value big enough?????
  final static int EXPANDCHARINDEX = 0x7E000000; // Expand index follows
  final static int CONTRACTCHARINDEX = 0x7F000000;  // contract indexes follow
  final static int UNMAPPED = 0xFFFFFFFF;

  final static int PRIMARYORDERMASK = 0xffff0000;
  final static int SECONDARYORDERMASK = 0x0000ff00;
  final static int TERTIARYORDERMASK = 0x000000ff;
  final static int PRIMARYDIFFERENCEONLY = 0xffff0000;
  final static int SECONDARYDIFFERENCEONLY = 0xffffff00;
  final static int PRIMARYORDERSHIFT = 16;
  final static int SECONDARYORDERSHIFT = 8;

  // ==============================================================
  // instance variables
  // ==============================================================
  private String rules = null;
  private boolean frenchSec = false;
  private boolean seAsianSwapping = false;

  private UCompactIntArray mapping = null;
  private Vector<Vector<EntryPair>> contractTable = null;
  private Vector<int[]> expandTable = null;
  private IntHashtable contractFlags = null;

  private short maxSecOrder = 0;
  private short maxTerOrder = 0;
}
